The present invention relates to a station control system for a driverless vehicle and, more particularly, to a system for controlling functional operations to be performed at one or more stations along the path of a driverless vehicle.
There are many known systems for guiding a driverless vehicle, including inertial guidance systems, active or passive wire guidance systems, optical guidance systems, and magnetic guidance systems. Absolute position indicators are commonly disposed along the vehicle guide path to provide periodic absolute position updates to the vehicle guidance system thereby increasing guidance accuracy and ensuring proper positioning of the vehicle. A variety of position indicators are commonly used, including lasers, optics, and floor-disposed position indicators. The floor-disposed position indicators provide the vehicle guidance system with the position of the vehicle in an absolute coordinate system. Such position indicators and the corresponding readers are expensive, require labor-intensive installation, and detailed surveying of their positions once installed. Moreover, absolute position indicators such as those described above are intended to assist in the guidance of the vehicle through absolute positioning updates which is in contrast to the functionality and purpose of the present invention.
In the past, driverless vehicle guidance systems have also used position indicators, such as an array of magnets, to identify when a vehicle is at a predetermined marked location or station along the guide path. In complex guidance systems, a plurality of magnets have been used in unique combinations to identify many different stations. However, the use of magnets as a means for marking predetermined stations along the guide path has several shortcomings. For example, the number of polarity combinations available from such magnets do not provide the statistical variation in unique and arbitrary identifiers that is desirable in complex driverless vehicle applications. Accordingly, there is a desire to provide a simple, flexible, and inexpensive station control system which overcome the shortcomings of the prior art.